Lumber positioning mechanism for edging machines



- ch 22, 1938. E sj s N 2,111,699

LUMBER POSITIONING MECHANISM FOR EDGING MACHINES Filed Feb 24, 1937 1 5 Shets-Sheet 1 INVENTORI EINAR FOLKE SGRENGELN BY 'mw;

ATORNEMS March 22, I938. F. SGRENSEN 2,111,699

LUMBER POSITIONING MECHANISM FOR EDGING MACHI NES Filed Feb. 24, 1957 3 Sheets-Sheet 2 I NVENTOR: EJNAR FOLKE SORENSEN ATIDRN 5M5 March 1938. E. F. SCJRENSEN 2,111,699

LUMBER POSITIONING MECHANISM FOR EDGING MACHINES Filed Feb. 24, 1957 5 Sheets-Sheet 3 :NvENToR EINAR FOLKECRENSEN ZZMZT Patented Mar. 22, 1938 UNITED STATES LUMBER POSITIONING MECHANISM FOR EDGING MACHINES Einar Folke Siirensen, Stockholm, Sweden Application February 24, 1937, Serial No. 127,494

- In Sweden March 4, 1935 9 Claims.

The present invention relates to improvements in the type of lumber positioning mechanisms for edging machines in which battens or boards are shifted before the edging operation into such a position in relation to the line or plane of cut that the waste of wood when edging the lumber is reduced to a minimum.

A mechanism of this kind is described in the U. S. patent specification No. 1,824,381 and comprises a number of selectors adapted to be brought into contact with the edge of the Work piece, members connected with said selectors and adapted to form clear of the work piece an inverted image of the contour registered. by the selectors, a displaceable positioning member adapted to be displaced to a position determined by the members forming said inverted image, and means cooperating with said positioning member adapted to adjust the work piece to a position determined by the new position of the positioning member. s

'Said selectors may be arranged either in two rows above each other, each row registering with the top or the bottom of the uneven edge of the work piece, or all the selectors may be arranged in a single row.

In this known mechanism said positioning member controlling the positioning of the work piece is moved into contact with the members forming the inverted image in the same direction in which the selectors, and thus also the imageforming members, move, whereby the pressure at the contact/ between said members tends to deform the image.

The present invention has for its object to improve such mechanisms so that the pressure exerted upon the image-forming members of the selectors by the positioning member will have no or only a slight tendency to deform said inverted image.

According to the invention this is accomplished by so arranging said positioning member that it will be displaced and pressed against the members forming the inverted image in a direction making an angle with the direction of motion of the selectors so that the back pressure acting on the selectors will be wholly or substantially absorbed by the friction acting between the positioning member and the members forming the inverted image.

According to anembodiment of the invention the positioning member and the members forming the inverted image are provided with cooperating abutment surfaces making an angle with the direction of motion of the selectors not exceeding the angle of friction was to obtain wedge action between said surfaces, when the positioning member is pressed against the members forming the inverted image.

In this way the members forming the inverted imageand the selectors will be exposed to very small forces acting in their direction of motion so that the selectors can be made weaker and lighter than previously. Their weight thus being reduced, their velocity of operation may be increased, and the size of the forces necessary for their operation will be reduced. Further no or only a small force is required for fixing the inverted image so that it will not be altered by the back pressure against it necessary for the positioning of the work piece, as this pressure practically is absorbed by the friction between the members forming the image and the positioning member. 7

A few embodiments of the invention are illustrated byway of example'in the accompanying drawings. 7

Fig. 1 shows a vertical cross-section through a part of an edging machine provided with a positioning mechanism according to the invention,

two rows of selectors being provided. 9

Fig. 2 is a plan view of the machine but with selectors arranged only in one row.

Fig. 3 is a side view of Fig. 2 with the upper part of the machine out through along the line III-III in Fig. 2.

Fig. 4 is a side view of a transmission device for gripping the work piece.

Fig. 5 is a plan view of Fig. 4,

Fig. 6 is an end View of Fig. 4. V

Fig. 7 is a diagrammatic plan View of a modified embodiment of the positioning ruler, when the turning of the work piece is not wanted.

Fig. 8 is a side view of Fig. 7.

Fig. 9 is a diagrammatic plan view of a modified selector shaped as an eccentric.

Fig. 10 is an end View of Fig. 9.

Fig. 11 is a side view of Fig. 9.

Fig. 12 shows diagrammatically a further modified selector.

In Fig. 1, 5| is the frame of the edging machine, 2|! the work piece, 2| a transporting chain for the work piece, and BI represents the linear plane of cut of the edging tool. II and. I2 designate a lower and an upper selector box, respectively in which a lower and an upper row of selectors I and 2 respectively are displaceably mounted so as to slide on the bottom plates of the boxes H and I2 respectively between guides 5 and 6 respectively transversely to the line of cut 6|. The

selectors 5, 6 are wedge-formed, their upper surfaces lb and 2b respectively having a taper of for example 1:5, and are provided with points la and 2a respectively projecting through holes in the sides of the boxes II and I2 turned towards the cutting line. Pulleys 1 and 8 mounted on the bottom plates of the boxes I I and I2 respectively being actuated by spiral springs 9 and I respectively strive to pull the selector points towards the cutting line by means of wires Ta and 8a atached at one end to the selectors. Shafts l3 and I4 journalled in the end walls of the boxes H and I2 are connected to the selectors by wires |3a and Ma. One end of the shafts l3 and I4 projects through the corresponding end wall of the boxes H and I2 respectively and is connected to a lever 35 by wires 33 and 34.

In each selector box a positioning ruler 3 and 4 respectively is provided. To the ends of the positioning rulers vertical shafts 24 and 24a are pivotally connected. Said shafts are provided with longitudinal flanges 55 (Figs. 2 and 3) sliding in vertical grooves in the end walls of the boxes H and I2. When the selectors are arranged in two rows, as in Fig. 1, the upper shaft 24a is screwed into the hollow lower shaft 24, whereby the distance between the two positioning rulers may be altered. The positioning rulers 3 and 4 are, above each selector, provided with wedge-shaped shoes 49 and 50 cooperating with the surfaces lb, 2b, whereby, in spite of wearing or minor faults of manufacture in the positioning rulers or the bottom plates, the positioning rulers always can be made to simultaneously abut 1 against all of the selector wedges, when the selector points are in a straight line. The shoes 49 and 50 cooperate with inclined surfaces lb, 2b so as to obtain wedge action, when any of the shoes are pressed against any of the surfaces lb, 2b. The shafts 24 project through the bottom plate of the lower selector box II and rest with their lower ends on the points 29a of the levers 29 which are provided with an eccentric cam surface 290 and. have their shafts 30 journalled in the frame The levers 29 are so balanced, if desired by means of springs, that their points 290. will be able to lift the positioning ruler above the highest point of the selector wedges, where the lifting is limited by stops.

On the shaft 42 journalled in the machine frame the levers 32 and 35 are keyed and the levers 38 and 39 and 39a pivotally mounted. From the lever 32 a pull wire 3| runs to and around the pulley 210,, which is fixed on the shaft 21 journalled in the machine frame, a spring, not shown, tending to turn said shaft clockwise in Fig. 1. At the ends of the shaft 21 cams 28 and 28a are fixed. In transversely running grooves on the side of the levers 39 and 39a stops are arranged at a distance from the centre of the shaft 42 of (in these cases) one-fifth of the distance from said centre to the points of attachment of the links 36 in correspondence to the inclination 1:5 of the selector wedges 2. These stops are adjustable by a screw 4| and a stop nut 490:, the points 46 of said stops lying so that, when the lever 39 is turned to the right, the point 46 will abut against the surface 290 and arrest the motion of lever 39. The rise of the eccentric surface 290 is such that, when the of the points 46 are adjusted according to the cutting line for every alteration of the cutting tool.

The links 36 connect the levers 39, 39a with slides I5, which slide in the machine frame 5| at right angles to the cutting line. Spiral springs 62 tend to pull the slides l5 towards the cut ting line. In a projecting part |5a of each slide l5 a cross-slide H is arranged so as to be slidable parallel with the cutting line. An inclined plane 60 (Fig. 2) secured in the frame 5| actuates a roller (not shown) mounted on the under side of the cross slide I! so that, when the slide 5 moves towards the cutting line, the cross slide l! is forced to slide towards the cutting tool parallel with the cutting line. A shaft I8 is rotatably but not slidably mounted in bearings ||a connected to the .slides II. On the shaft l8 the gripping arms 19 for the work piece are secured.

Their adjustable points |9a enter into the work piece when the shaft I8 is turned clockwise. Another cross-slide I6 is slidably mounted in the projecting part |5a of each slide l5 so as to slide parallel with the cutting line. When the lever 38 is turned to the left in Fig. 1 the link 31, the double-armed lever 52, journalled in the machine frame by means of the shaft 59, and the link 52a will pull the cross-slide l6 parallel with the cutting line so that a roller I81), secured to an arm |8a projecting from the shaft l8, will run in the groove I612. provided in the slides and be forced downwards, thus turning the arm |8a downwards so that the shaft 8 will be turned (Figs. 4-6) In the frame 5| the shaft 45 (Figs. 1 and 2) is journalled, and is mechanically actuated counterclockwise so as to make one revolution for each dog 2|a on the feeding chain 2| brought into action. On the shaft 45 the following eccentrics are secured.

l. The cams 44, one at the lever 39 and one not shown at the lever 39a, which cams determine the moments at which said levers are to be moved forwards and backwards.

2. The cam 32a, which controls the time for the movements of the lever 32 and thus those of the shaft 42 and the lever 35.

3. The cam 38a, which controls the movements of the lever 38.

4. Two cams, not shown, which control the locking and releasing of the shafts 30 by means of other devices (not shown).

All the cams on the shaft 45 are mounted so that they act at the moments set forth in the description below of the operation of the mech-- anism.

Below the bottom plate of the selector box levers 25 are journalled at 25a and are actuated by the springs 56 (Fig. 3). The levers 25 are controlled by the cams 28 fixed to shaft 21. When the cams 28 have been turned so far that they do not support the levers 25 any more, the springs 56 press down said levers so that their forked end 25b will be pressed down against a projection 26 on the shaft 24 and thus press down the shaft 24 and the positioning ruler or rulers 3, 4, until the latter at two points abut against the selector wedges 2. As the work piece 26 always is placed in the machine with its fore end at the same place, an adjustable counterweight 51 is provided on the rear (seen to the left in Fig. 3) lever 25. By adjusting the position of the counter-weight the downward pressure on the shafts 24 and thereby on both ends of the positioning rulers will be changed accordinglyand this adjustment should be so carried out that the downward pressure on the ends of the rulers will be in reversed proportion to the v distance from the centre of the work piece to r lever 52, and link 52a (Figs. 4-6).

the ends of the positioning ruler 3. This adjustment of the pressure may alternatively be effected in other Ways by means of springs or weights. The counterweight shown in the drawings is only an example of such an arrangement.

An adjustable stop 66 provided with openings for the selector points is arranged between the cutting line and the selector boxes to limit the displacement of the lumber edge past the cutting line. The stop 66 is shown as a vertical longitudinal plate, the ends of which are supported by links 6611 slidably mounted on plates 66b connected to the selector box .H or the machine frame. The links 66a are-provided with pivots 66c sliding in slots 47, 48 in the plates 66b for adjustingthe position of the stop 66. For long work pieces and for such having a more irregular edge, the stop 66 is positioned farther away from the cutting line than for shorter and more regular 'work pieces. By reducing or increasing the length of the wires 33 and 34 the selectors are allowed to project so far that their points will come in alignment with the stop 66 inthe position of departure, i. e. when the lever 35 is turned fully back. Thus the extent of the movements of the selectors is reduced and thus also the time necessary for bringing the selectors into contact with the edge of the lumber. The moment when the cams 28 release the levers 25 is adjusted by increasing or reducing the length of the wire 3! so that the positioning rulers are pressed down against the selectors as soon as these have been fully projected towards the work piece. 58 designates the pressure rollers of the edging machine working against the upper side of the lumber. Such selectors as are not needed are pulled back and locked in this position, as shown for the three left selectors in Fig. 2.

The machine works in the following way:

The work piece 20 is pushed in on the feeding chain 2! below the raised gripping arms I9 so far past the cutting line that every cavity in the lumber edge has passed the cutting line, this motion, however, being limited by the stop 66. The counter-clockwise rotating shaft 45 causes first the cam 38a to turn the lever 38 so far to the left in Fig. 1 that the cross-slide I6 is pulled a desired distance forwards towards the cutting tool, for example 12 cms., the lever 36 acting as described on the slide I6 by means of link 31, After two cms. of this movement the groove l6a in the slide l6 will have turned the shaft I8 clockwise by forcing down the roller I81) on the arm l8a secured on the shaft I8, so that the latter is turned clockwise, the gripping arms l9 now being turned downwards so that the gripping points l9a will enter into the-work piece. At the moment when the work piece is gripped by the gripping arms l9, the shaft 45 has been turned so far that the cam 32a secured to it, which until now has kept the lever 32 (and consequently also the lever 35) to the left in Fig. 1 and thus also the selectors pulled back, releases this lever 32. Under the influence of the springs 9 and l 0 acting upon the selectors l and 2, the wires [3a, Ma, 33 and 34 and the spring forces acting on the shaft 21 and thus through the wire ,3! on the lever 32, begin to turn the levers 38, 32 to the right .(Fig. 1). The selectors will now slide to the right until their points la, 2a abut against the lumber edge.

During the continued turning movement clockwise of the shaft 21, the cams 28 will release the levers 25, which then, actuated by the springs 56, by pressure on the projections 26 press the shafts 24, 24a downwards until the positioning rulers 3 and 4 at two points abut against the shoes 49 of the selector wedges. The positioning rulers will then occupy the position, which is indicated for the positioning ruler 3 in Fig. 3.

As stated above the selector points la, 2a were in line in their position of departure. Consequently, the relative displacements of the selector wedges l, 2 towards the work piece until the selectors register with the edge of the latter will correspond to the contour of the edge as registered. If the inclination of the surfaces lb, 21) is l 5, it follows that in a vertical plane laid through the selector wedges the crests of the selector 7 wedges will form in relation to each other an inverted image in the scale 1:5 ofthe contour of the lumber edge as registered by the selectors. Thus this is the case also with the vertical plane through the positioning rulers 3, 4. When the rulers 3, 4 are depressed as described above two shoes 49 will abut against the wedges of those selectors on each side of the centre of the work piece which have registered the deepest cavities in the lumber edge. This is illustrated in Figs. 2 and 3, and consequently the ruler 3 will occupy a new inclined position, the vertical displacement of which in relation to the position of departure determines the extent of the lateral displacement of the work piece, while the extent of inclination of the ruler determines the extent of the turning motion lengthwise of the lumber so that the cutting tool will edge the lumber along a line or plane that tangentially touches said deepest cavities of the edge, as will be explained below.

At this stage in the operation of the mechanism the shaft 45 has been revolved so far that two cams not shown secured at its ends give the impulse to the locking of the shafts 36 (and thus also of the levers 29) in their present position. Fig. 1 shows the device at this moment.

These now locked positions of the levers 29, as being determined by the two ends of the rulers 3, 4, will thus be dependent on both the vertical displacement and the inclination of the rulers. As

the rise of the eccentric surface 290 as described above corresponds to the vertical motion of the points 29a, and the surfaces 290 cooperate with the stops 46 on the levers 39, the relation of the distances from the stop 46 or the point of attachment of the links 36 to the shaft 42, being the same as the ratio of inclination of the selector wedges I, 2 (1:5), and since the stops 66 and the position of departure of the rulers 3, 4 have been set in relation to the position of the cutting line, it is apparent that the motion of the links 36 from the levers 39 being released until the levers are arrested by the stops 46 will be in such a relation to the new positions of each end of the rulers 3, 4, that the slides i 5 and thus the gripping arms 59 will be given such lateral motions that the work piece will be brought to the desired position.

The levers 39 are released when the shaft 45 has been revolved so far that the rollers 43 slide down into the recesses of the cams 64, whereupon the levers are pulled to the right by the spiral springs 62 acting upon the slides until the points of their stops 46 are stopped by the eccentric surfaces 23c of the levers 29. The slides i5 will thus have displaced and/or turned the work piece by means of the grippers l9 so that,

when afterwards in this position it is moved past the cutting tool by the chain ZI, the cutting line GI of this tool will just touch the bottom of the two deepest cavities in the work piece edge at opposite sides of the centre of the work piece.

Simultaneously with or somewhat before the lateral displacement of the work piece, the cam 32a actuating the lever 32 begins to turn the shaft 12 and thus the lever 35 to the left so that the selectors are returned to their position of departure.

The feeding chain 2| now carries the work piece 26 past the cutting tool below the pressure rollers 58, the gripping arms I9 carrying along the shaft I8, the bearings Ho and the slides I'I. When the fore end of the work piece has arrived below the rollers 58, the roller I 8b has raised the arm ISa due to the upwardly turned curve of the groove Hi0. now being reached, thus turning the shaft I8 counterclockwise so that the points I9a are withdrawn from the work piece, which then continues its way on the feeding chain being kept in position by the pressure rollers and the dog 2 la.

The work piece in this way being released, the shafts 36 are released, and the levers 38 and 39 are forced back to the starting point by their respective eccentric during the continued turning motion of the shaft 45. Hereby the slides l5 and i'lthe latter by means of the slide l6are pulled back, and the positioning rulers rise to their starting points, whereupon the machine is ready to receive the next work piece.

If the device is intended for handling such regularly shaped lumber that a satisfactory result is obtained without turning the Work piece, one or both of the above described positioning rulers 3 and i be substituted by rulers of such a construction that they will always maintain horizontal position, whereby they only will abut against the selector that reaches the highest level in the reversed picture, i. e. is foremost projected. In the position of the selectors, shown in Fig. 3, this would be the fifth selector from the left.

One way of always keeping the ruler horizontal is to give it a [-shape (Figures 7 and 8), Wherein the ruler itself is designated by 3 and the shanks 3a of the channel are journalled in the machine frame at 63 and 63a. Especially for longer rulers of this construction it might be advisable to support them to avoid swinging. This may for instance be effected by connecting the ruler by means of two or more pivotable links 64 with a slide 65 sliding in dove-tail grooves in the machine frame.

In this embodiment it is not necessary to hold the piece by means of gripping arms. The work piece may be fed in along a guide, which, by means of the reversed picture of the lumber edge, is adjusted at a distance from the cutting line that corresponds to the deepest cavity in the lumber edge. The construction may in this case be simplified by removing the cross-slides I? and I6 and the shaft I8 with their levers and eccentrics and by securing the guide ruler 6'5 directly on the slides I5. Where the edging machine permits of supporting the levers 39 in bearings close to the vertical line through the ruler 66, said ruler may be fixed directly on the levers 39. Further, as the motions of both levers 39 in this case also will be identical it is possible to make the device cheaper by using only one shaft 24 and one lever 29 for limiting the lateral displacement, the shaft 24 being preferably fixed close to the middle point of the positioning ruler 3 and the lever 29 arranged accordingly.

In this embodiment the device works upon the same principle as in the previously described more complete embodiment. The operator keeps the lumber edge pressed against the guide ruler 66, while the reversed picture is formed and while the lever 291s adjusted and locked through the action of the positioning ruler and the shaft 24. Upon the lateral displacement, the guide ruler 66 will then reach a distance from the cutting line equalling the depth of the deepest cavity in the lumber edge, so that, if the work piece is fed past the cutting tool with the lumber edge pressed against this ruler, the cutting line will just touch the bottom of the deepest cavity in the lumber edge.

Figs. 9 to 11 show another embodiment of the selectors. The selector consists in this case of the eccentric IllI provided with an upper inclined abutment surface for the positioning ruler I03. The selector is fixed to the shaft 19 journalled in the machine frame, which shaft carries the selector arm 61, which with its point 67a protrudes upwards through a slot in the feeding table 'II. The shaft I0 tends by the pressure of a spring (not shown) to be turned counter-clockwise until this turning motion is limited by stops or the like, when the selectors have swung forwards to a suitable distance ahead of the guide ruler I66.

The positioning ruler I93 (Figs. 9 to 11), as in the previous example, determines the positioning of the lever 29 by abutting against the eccentric I9I and consequently also determines the lateral displacement of the lumber piece by means of the guide ruler I66.

As the selectors in this case swing back, they may in the starting position occupy their most advanced position and be pushed back by the pressure of the lumber edge when this is pushed into the device towards the guide ruler I66.

This embodiment is specially suitable for smaller devices with the selectors arranged in one row only, as the resistance against pressing them back is not so great as to make the operator tired. With these selectors the device is further simplified, as the lever 35 with its eccentric, pull Wires etc. are omitted.

If this embodiment of the selectors is used in the above described simplified device, where no turning'of the work piece takes place, such a small force is required for operating the device, that it may be obtained for instance from a pedal, the device then working in the following way. The lumber edge is pressed against the guide ruler I66. The pedal is depressed. During the first part of the lowering of the pedal, the positioning ruler I03 is lowered so that it rests on the highest selector, the lever 29 being automatically adjusted by means of the shaft 24. During the next part of the lowering of the pedal, the shaft 39 and thereby the lever 29 are locked in their present position. During the third and last part of the lowering of the pedal, the lever 39 is actuated so that it is pulled forwards until its stop 46 abuts against the eccentric surface of the lever 29. The guide ruler I 66 now lies in a line parallel with the cutting line at a distance from the same equalling the depth of the deepest cavity of the lumber edge. The operator now pushes the work piece along with its edge against the guide ruler I66 past the cutting tool, the cutting line just touching the bottom of the deepest cavity of the lumber edge. The pedal is now released, whereupon the device returns to the starting position, ready to receive the next work piece.

Fig. 12 shows a further embodiment of a selector. The selector is formed as an eccentric 20I against the circumference of which the positioning ruler 103 is adapted to abut. A gear 202 mounted on the shaft 203 of the selector is in mesh with a gear rack 72 provided with points 204 registering the edge of the work piece.

Having now particularly described the nature of my invention and the manner of its operation what I claim is:

1. Mechanism for positioning lumber in edging (machines in relation to the line or plane of out, comprising a number of selectors adapted to be brought into contact with the edge of the work piece, members connected with said selectors and adapted to form clear of the work piece an inverted image of the contour registered by the selectors, a displaceable positioning member adapted to be displaced to a position determined by the members forming said inverted. image, means cooperating with said positioning member adapted to adjust the work piece to a position determined by the new position of the positioning member, said positioning member being arranged to be displaced and pressed against said members forming the inverted image in a direction making an angle with the direction of motion of the selectors so that the back pressure acting on the selectors will be wholly or substantially absorbed by the friction acting between the positioning member and said members forming the inverted image.

2. Mechanism according to claim 1, character-- ized in that said positioning member and said members forming the inverted image are providedwith cooperating abutment surfaces making an angle with the direction of motion of the selectors not exceeding the angle of friction so as to obtain Wedge action between said surfaces when the positioning member is pressed against the members forming the inverted image.

3. Mechanism according to claim 1, characterized in that the members forming the inverted image are provided with wedge-like portions having a plane surface cooperating with the positioning member and making an angle with the direction of motion of the selectors not exceeding the angle of friction.

4. Mechanism according to claim 1, characterized in that the members forming the inverted image are shaped as eccentrics, the circumference of which cooperate with the positioning member, said eccentrics being geared to selector points registering the edge of the work piece.

5. Mechanism according to claim 1, characterized in that the positioning member extends transversely to the selectors and is arranged movable in a plane substantially perpendicular to the direction of motion of the selectors.

6. Mechanism according to claim 1, characterized in that the positioning member extends transversely to the selectors and is arranged to be movable parallel to itself in a plane substantially perpendicular to the line of motion of the selectors.

7. Mechanism according to claim 1, characterized in that the positioning member extends transversely to the selectors and is arranged to be movable in a plane substantially perpendicular to the direction of motion of the selectors, both parallel to itself and about an axis parallel to the selectors.

8. Mechanism according to claim 1, characterized in that the members forming the reversed image are adjustable independently of each other in relation to the part of the selectors registering the edge of the workpiece.

9. Mechanism according to claim 1, characterized in that the positioning member extends transversely to the selectors and is arranged to be movable parallel to itself in a plane substantially perpendicular to the line of motion of the selectors and is provided with a number of adjustable parts, each one cooperating with one of the members forming the inverted image.

EINAR FOLKE SOREN SEN. 

